160 THE STRUGGLE FOR EXISTENCE 



135. Wood, F. E. 1910 A study of the mammals of Champaign Country, 



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136. Woodruff, L. L. 1911 The effect of excretion products of Paramecium 



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137. Woodruff, L. L. 1912 Observations on the origin and sequence of the 



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138. Woodruff, L. L. 1914 The effect of excretion products of Infusoria on 



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